| Message ID | 155259748531.31886.6568534900832262149.stgit@magnolia (mailing list archive) |
|---|---|
| State | Accepted, archived |
| Headers | show |
| Series | xfsprogs-5.0: fix various problems | expand |
On 3/14/19 4:04 PM, Darrick J. Wong wrote: > From: Darrick J. Wong <darrick.wong@oracle.com> > > The fzero_f function doesn't check that there are enough non-switch > parameters to supply offset and length arguments to fallocate. As a > result, we can walk off the end of the argv array and crash. A > secondary problem is that we don't use getopt to detect the -k, eek > which is > not how most xfs_io commands work. no it is not. :) > > Therefore, use getopt to detect the -k argument and rewire the offset > and length interpretation code to check optind and use argv correctly. > This bug is trivially reproduced by "xfs_io -c 'fzero -k 0' /some/file". > > Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Eric Sandeen <sandeen@redhat.com> > --- > io/prealloc.c | 20 +++++++++++++------- > 1 file changed, 13 insertions(+), 7 deletions(-) > > > diff --git a/io/prealloc.c b/io/prealloc.c > index 9a372bae..6d452354 100644 > --- a/io/prealloc.c > +++ b/io/prealloc.c > @@ -285,18 +285,24 @@ fzero_f( > { > xfs_flock64_t segment; > int mode = FALLOC_FL_ZERO_RANGE; > - int index = 1; > + int c; > > - if (strncmp(argv[index], "-k", 3) == 0) { > - mode |= FALLOC_FL_KEEP_SIZE; > - index++; > + while ((c = getopt(argc, argv, "k")) != EOF) { > + switch (c) { > + case 'k': > + mode |= FALLOC_FL_KEEP_SIZE; > + break; > + default: > + command_usage(&fzero_cmd); > + } > } > + if (optind != argc - 2) > + return command_usage(&fzero_cmd); > > - if (!offset_length(argv[index], argv[index + 1], &segment)) > + if (!offset_length(argv[optind], argv[optind + 1], &segment)) > return 0; > > - if (fallocate(file->fd, mode, > - segment.l_start, segment.l_len)) { > + if (fallocate(file->fd, mode, segment.l_start, segment.l_len)) { > perror("fallocate"); > return 0; > } >
diff --git a/io/prealloc.c b/io/prealloc.c index 9a372bae..6d452354 100644 --- a/io/prealloc.c +++ b/io/prealloc.c @@ -285,18 +285,24 @@ fzero_f( { xfs_flock64_t segment; int mode = FALLOC_FL_ZERO_RANGE; - int index = 1; + int c; - if (strncmp(argv[index], "-k", 3) == 0) { - mode |= FALLOC_FL_KEEP_SIZE; - index++; + while ((c = getopt(argc, argv, "k")) != EOF) { + switch (c) { + case 'k': + mode |= FALLOC_FL_KEEP_SIZE; + break; + default: + command_usage(&fzero_cmd); + } } + if (optind != argc - 2) + return command_usage(&fzero_cmd); - if (!offset_length(argv[index], argv[index + 1], &segment)) + if (!offset_length(argv[optind], argv[optind + 1], &segment)) return 0; - if (fallocate(file->fd, mode, - segment.l_start, segment.l_len)) { + if (fallocate(file->fd, mode, segment.l_start, segment.l_len)) { perror("fallocate"); return 0; }